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/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode(int x) { val = x; }
 * }
 */
class Solution {
    public ListNode deleteNode(ListNode head, int val) {
        // 假如頭結(jié)點(diǎn)就是要?jiǎng)h除的節(jié)點(diǎn),直接返回下一個(gè)下一個(gè)節(jié)點(diǎn)
        if(head.val == val){
            return head.next;
        }
        // 初始化前驅(qū)指針和當(dāng)前指針
        ListNode pre = head;
        ListNode cur = head.next;
        // 當(dāng)當(dāng)前節(jié)點(diǎn)結(jié)點(diǎn)不為空卻不是要輸出的值時(shí),遍歷鏈表
        while(cur != null && cur.val != val){
            pre = cur;
            cur = cur.next;
        }
        // 當(dāng)遍歷到要?jiǎng)h除的值時(shí)
        if(cur != null){
            // 刪除指定的節(jié)點(diǎn)
            pre.next = cur.next;
        }
        // 返回頭結(jié)點(diǎn)(整個(gè)鏈表)
        return head;
    }
}